Systems and methods for high voltage rating thin film sensors

ABSTRACT

Improvements in thin film sensors are disclosed. These can be used for aircraft applications. Dielectric isolation washers can be provided between a pressure sensor and an exterior metal housing of a sensor assembly. In this manner, high voltage inputs from a lightning strike or other source that reach the sensor housing are not transmitted to the sensor. Dielectric washers, insulators, and potting compounds can thus isolate a metal thin film pressure sensor from adjacent metal components (e.g., using non-conducting insulating materials like Torlon, zirconia and nylon). Besides their high dielectric strength, these materials exhibit compressive strength and resistance to wear, creep and corrosion. Desirable thicknesses for these components are provided. The described thin film pressure sensor embodiments can attain a dielectric rating of 1500 VAC.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/560,280, titled “SYSTEMS AND METHODS FOR HIGH VOLTAGE RATING THINFILM SENSORS” filed Sep. 4, 2019. Any and all applications for which aforeign or domestic priority claim is identified in the Application DataSheet of the present application are hereby incorporated by referenceunder 37 CFR 1.57. The entire disclosure of each of the above-identifiedapplications is incorporated by reference herein and made part of thisspecification, for all purposes, for all that each contains.

FIELD

The present disclosure relates to systems and methods for thin filmpressure, temperature and flow sensors used in various aircraft andindustrial systems.

BACKGROUND

Aircraft systems and pressure sensors installed on them can be subjectedto high voltage inputs from lightning strikes that can damageunprotected sensors. Since sensor housings are typically metal(stainless steel) and installed on other metal assemblies (such as apump or manifold), the entire system may be conductive and susceptibleto these high voltage inputs. Therefore, the sensors need to protectedand isolated or electrically insulated from adjacent metal components.Typical thin film pressure sensors are rated to withstand 500 VAC ofpower.

However many aircraft systems require sensors to survive 1500 VAC ofpower spikes. Moreover, aircraft pressure sensors are routinelysubjected to harsh environmental conditions. Since these sensors oftenmeasure hydraulic pressure, the sensors can be exposed to the causticnature of some hydraulic oils. Also, pressures often reach 4500 psi andtemperatures can range between −55° C. to 200° C., causing sensorcomponents to be subjected to substantial compressive forces, wear,creep and distortion. The sensors may also be subject to impulsepressure cycling, which can result in sensor failure due to fatigue.

Two types of pressure sensors are appropriate for use on aircraft: MEMS(micro-electromechanical) and Thin Film sensors. Both types usepiezoresistive strain gauges to convert pressure into an electricaloutput. The most common is a MEMS sensor. The strain gauge for thissensor is molecularly bonded on to a silicone substrate and is rated to1500 VAC. In this case, the silicone acts as an insulating material forthe strain gauge. However, due to its construction, this type of sensoris more expensive than a thin film sensor and cannot come in contactwith harsh system medias being measured, like fuel or hydraulic oils.Therefore, it is housed in a sealed metal pressure capsule filled withsilicone oil and covered by a thin stainless diaphragm. In this case,the media pressure is applied to the stainless diaphragm and transferredby the silicone oil to the MEMS sensor. A second type of sensor is ametal thin film sensor. This sensor has a metal housing and metaldiaphragm on which the strain gauge sensor is directly deposited. One ofthe main benefits of this construction is that the measured media can beapplied directly to the diaphragm under the strain gauge. However, dueto its metal housing and diaphragm, this type of sensor will notwithstand 1500 VAC and has a lower dielectric rating of approximately500 VAC.

A metal thin film sensor uses changes in resistance in a Wheatstonebridge strain gauge structure, due to the metal diaphragm deflection, tomeasure pressure. As noted, the base 14 of the sensor body is made ofstainless steel. The resistance structure is produced byphotolithography. Thin film measuring cells stand out due to theirexcellent resistance to pressure peaks and bursting pressure. Extremelyhigh pressures can be measured—even when exposed to high shock andvibration loads. In metal thin film technology, four resistors areinterconnected to create the Wheatstone bridge.

SUMMARY

To solve the problems associated with previous thin film pressuresensors, in certain embodiments, dielectric isolation washers areprovided between the pressure sensor that senses the system pressure andthe interior surfaces of the exterior metal housing and other pressurefittings of the system. That way, high voltage inputs from a lightningstrike that reach the sensor housing are not transmitted to the sensor.In some embodiments, the dielectric washers isolate the metal thin filmpressure sensor from all adjacent metal components in the assembly withnon-conducting insulating materials like Torlon, Zirconia and Nylon.Torlon is a registered trademark of the Solvay company, and is anaerospace grade material that has excellent insulative and durabilityfeatures. It can be used as an electrical insulator due to its highdielectric strength. It has excellent compressive strength andoutstanding resistance to wear, creep and chemicals. In order to attaina dielectric rating of 1500 VAC, the thickness of these isolationwashers and insulators is increased. In the embodiments described below,appropriate thicknesses are set forth.

Furthermore, the thin film pressure sensors of some describedembodiments are mounted within the housing of the system, using theinsulators, in a manner which allows them to “float” within the housing,meaning there are no metal-to-metal connections of the sensor assemblyin their mounting. Moreover, the sensors of the present embodiments aremuch less expensive and have several technical advantages over MEMSpressure sensors. The present thin film sensors have an operatingtemperature range from −55° C. to 200° C., versus a MEMS pressure sensorrange of −40° C. to 125° C. The present thin film sensors are also lesscomplex (have fewer parts) than MEMS sensors, are easier to work with,and are more stable at extreme temperatures. In addition, the sensorsare durable and rugged, given their steel housing. On the other hand,notwithstanding their conductive metal housing, achieving a dielectricrating of 1500 VAC overcomes a significant disadvantage of prior thinfilm sensors and provides an important advantage over MEMS sensors inaircraft applications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side cross-sectional view of one embodiment of the presentthin film pressure sensor assembly.

FIG. 2 is an exploded view of the thin film pressure sensor assembly ofFIG. 1 illustrating most of its individual components.

FIG. 3 is an exploded view of the sensor assembly similar to FIG. 2 butin cross section, thus illustrating the dimensional advantages ofcertain components.

DETAILED DESCRIPTION

For purposes of the present description, certain aspects, advantages,and novel features of the invention are described herein. It is to beunderstood that not necessarily all such advantages may be achieved inaccordance with any particular embodiment of the invention. Thus, forexample, those skilled in the art will recognize that the invention maybe embodied or carried out in a manner that achieves one advantage orgroup of advantages as taught herein without necessarily achieving otheradvantages as may be taught or suggested herein. The advantages of thepresent embodiments can be carried out with respect to other sensors,such as temperature and flow sensors, in addition to pressure sensors.

Systems, methods, and processes, which represent various embodiments,will now be described with reference to the drawings. Variations to thesystems, methods, and processes which represent other embodiments willalso be described. Thus, the present invention is not limited by thetype of environment or application in which the systems, methods, andprocesses are described herein, meaning that they may be successfullyutilized in connection with industries other than the aircraft industry.

With reference to FIGS. 1 and 2, the features for at least oneembodiment will be described. The thin film pressure sensor assembly 10comprises a stainless steel body or housing 12 which is situated on theright hand side of FIG. 1. The left hand side illustrates othercomponents less relevant to this disclosure. The stainless steel body orhousing contains various components which contribute to the pressuremeasurement, containment and/or which insulate the structural componentsso as to withstand high voltage spikes.

The housing 12 has two segments—a lower base 14 and an upper cover 16.The base 14 is shown best in FIG. 2 and the cover 16 is seen best inFIG. 1 and not shown in FIG. 2 because of the exploded nature of thatfigure. The lower base 14 supports the sensor assembly 10, includinginternally threaded assembly platform 18, and the upper cover 16 seals,surrounds and protects the sensor assembly 10 from the externalenvironment. Situated within the threaded assembly platform 18 is thestainless steel sensor pedestal 20, including the sensor itself 22,situated atop the pedestal 20. At the bottom of the lower base 14 islocated a pressure port 34 where the fluid or pneumatic pressure entersthe sensor assembly 10 from the aircraft system and is applied throughthe sensor pedestal 20 to the thin film sensor 22. As depicted in FIGS.1 and 2, the thin film sensor 22 and pressure port pedestal 20 assemblyare isolated from all adjacent metal components by non-conductiveTorlon, zirconia or nylon insulators 28, rubber or silicone O-rings 30,and/or a potting compound 54. By identifying a minimum thickness forthese materials surrounding the thin film sensor 22 and the pressureport pedestal assembly 20 present sensor assembly 10 embodiments areable to achieve a dielectric rating of 1500 VAC. As noted above, variouscombinations and thicknesses of these dielectric materials are withinthe scope of this application. As explained in more detail below, theinsulators, which may comprise insulator washers, comprise upper andlower insulator washers 28 a and 28 b, as well as pressure portinsulator or insert 28 c. A fourth insulator washer 28 d is describedbelow in conjunction with the sensor 22 and a register 40. Two O-ringseals 30 a and 30 b are shown in FIGS. 1 and 2.

As shown in FIG. 1, the pressure port 34 receives the fluid which is thesubject of the pressure measurement. The port 34 opens into acylindrical stainless pressure port pedestal 20 at the top of which islaser welded the thin film pressure sensor 22. The pressure port 34 andpedestal 20 are shown particularly well in the cross-sectional view ofFIG. 1. The pedestal 20 includes a disc-shaped skirt 21 or waist, whichexhibits a cylindrical shape, for mounting the pedestal 20 within thesensor body or housing 12. The top of the thin film sensor 22 containsthe Wheatstone bridge strain gauge which is wire bonded and coupled tothe circuit board 36 above the sensor 22, as illustrated in FIGS. 1 and2. The housing cover 16 also covers or encloses other componentsincluding various other circuit boards 38 as shown.

The thin film pressure sensor assembly 10 is mounted and containedwithin the housing 12 by a sensor assembly register 40 best illustratedin FIG. 2. Sensor assembly register 40 is also cylindrical in shape andexhibits external threads 42 which mate with the internal threading 44of the platform 18 of the housing base 14 to register and mount thepressure port pedestal 20 within the housing 12. Two bolts 46 areutilized to mount the circuit board 36 to the top of the sensor assemblyregister 40 and lock the register 40 in place as illustrated. Torloncaps 47 are used to cover the heads of the bolts 46. These two bolts(only one of which is shown in FIG. 1) or screws 46 are used to mountand retain the circuit board 36 to the top of the sensor assemblyregister 40. This is important because the thin film sensor is wirebonded with small 0.001 in diameter wires to this circuit board andcannot move once assembled. This connection allows the electrical outputfrom the thin film sensor to be transferred to circuit board 36 and thensequentially to the upper circuit boards 38.

These are the typical components of a thin film pressure sensor includedwithin a stainless steel housing. However, in this embodiment, multipleinsulators, washers, and or O-ring seals are added and utilized toprovide a high voltage rating for the sensor. It will be understood thatinsulators and other dielectric components of different quantities andshapes may be utilized and are within the scope of the presentdisclosure and that the embodiment illustrated and described is only onepossible embodiment of the present invention.

Referring again to FIGS. 1 and 2, near the pressure port area 34, anylon insert insulator 28 c is positioned between the base 14 and thepedestal 20. This insulator 28 c can be made of nylon or similardielectric material. At least two O-ring ring seals 30 a and 30 b aresituated just above the nylon insert insulator 28 c, one of which 30 bsurrounds the base of the pedestal and the second 30 a surrounds a lowerinsulator washer 28 b. Lower insulator washer 28 b is also preferablymanufactured from a high dielectric, corrosive resistant material. Twosuch materials are nylon or zirconia; however, in this embodiment thelower insulator washer is made from Torlon. As illustrated in theseFIGS. 1 and 2, in addition to the lower insulator washer 28 bsurrounding the pedestal 20, an upper Torlon insulator washer 28 a isalso utilized. These washers sandwich the skirt 21 between them andprovide at least in part the desired electrical insulation and isolationas described above.

Upper insulator washer 28 a also includes an upper shoulder 50 portionwhich mates within the assembly register 40 as best illustrated inFIG. 1. A fourth insulator washer 28 d is situated within the housing 12near the pressure sensor 22 itself. This fourth insulator washer 28 d isbest illustrated in FIG. 2. It also includes a lower shoulder 52 whichmates within an upper recess in the assembly register 40 and,advantageously, surrounds the pressure sensor 22 itself. These fourinsulator washers 28 a-28 d provide important electrical insulation ofthe thin film pressure sensor 22. As noted above, other washer shapesand quantities are within the scope of the present invention.Advantageously, this fourth insulator washer 28 d also insulates thebolts 46 which mount the circuit board 36 to the pressure sensorassembly.

One of the advantages of the present embodiment is the use of Torloninsulator washers. Various types and sizes of such insulator washers maybe utilized. Such washers may be manufactured from an extrusion orinjection molding process, or a compression molding process using apolymer formulation. One such formulation is a polyimide. Such washersoffer excellent compressive strength, electrical insulation, and impactstrength. This material exhibits the ability to carry loads over a broadtemperature range and is resistive to abrasive wear and corrosion.

With reference to FIG. 1, another advantage of the present embodiment isthe use of a potting material 54 which also exhibits importantinsulation qualities. The potting material 54 is placed within theassembly housing 12 and generally is situated between the sensorassembly components and the interior wall of the cover 16. This materialserves to hold the components of the sensor assembly in place while alsoproviding an insulation advantage. Thus, one preferred type of pottingmaterial is Epoxylite 813-9. Epoxylite is a trademark of the EpoxyliteCorporation.

Several types of potting compound may be used in the presentembodiments. One preferred compound is an ultra-high temperature pottingresin that is manufactured from a two-part epoxy system. The preferredpotting compound packed around the sensor and pedestal is Epoxylite#813-9. This is a specific potting compound which incorporates a hightemperature potting resin with high chemical resistance and gooddielectric resistance. Potting material 54 is also placed in the upperportion of the housing 12 within the cover 16 to hold various circuitboards 38 in place.

Thus, with reference to FIG. 1, it will be noted that thecircumferential dimension of various components does not extendcompletely to the interior surface of the housing 12 or cover 16. Thisincludes the upper and lower insulator washers 28 a, 28 b as well as thethird and fourth insulator washers 28 c, 28 d. Therefore, space isprovided for the potting material 54 to hold these components in placeand to insulate them from the stainless steel material of the base 14and the cover 16. Moreover, potting material 54 also is situated betweenthe pedestal skirt 21 and the housing cover 16. The pedestal skirt 21serves as an enlarged flange formed on the pedestal 20 in order to allowwashers 28 a, 28 b to insulate the pedestal 20 and secure it within thehousing 12.

Advantages and Methods

The advantages described above are achieved, at least in part, by asystem and method of mounting the sensor assembly within the housingusing insulative components (such as the various insulative componentsmentioned). It should be noted that variations in the number andplacement of such components are possible and within the scope of thepresent application. Furthermore, the insulative components are situatedwith respect to the pedestal/sensor assembly 20, 22, and with respect tothe pressure register 40, in order to achieve the insulative, floatingmounting of the pedestal/sensor assembly. These components, togetherwith the design of the pedestal and register, provide a mounting whichis in the nature of a friction fit or friction mount within the housing,as shown in the figures and described herein. Thus, even without a fixedweld to the base or other metallic members, the pedestal/sensor assemblyis retained securely within the housing.

Certain embodiments described herein enjoy various advantages withrespect to the manner in which the thin film sensor is mounted. As notedabove, the sensor is welded to the top of an elongated pressure portpedestal. However, unlike previous designs, the pressure port pedestalincorporates a “floating” mounting design in which, other than thissingle weld, there is no other fixed mounting of the sensor or thepedestal with respect to the housing. Of course, the pressure portpedestal/sensor assembly is not literally “floating” in thelighter-than-air sense, but rather it floats, in the dielectric sense,within the housing in that it (along with its pedestal 21) is notrigidly or fixedly mounted to any other rigid component, as in previousdesigns. Furthermore, other than the weld to the top of the pedestal,there are no metal-to-metal connections.

In previous designs, the sensor was welded directly to the top of ashort 0.090-0.095 inch pedestal which was integrated into or part of athreaded bottom pressure fitting. This pressure fitting was theninstalled (e.g. threaded) directly into the corresponding pressurizedaircraft system (e.g. hydraulic manifold, filter, pump, actuator, etc.)that was to be monitored by the sensor. In other words, previous designsdid not have the floating pedestal mounting or the sensor assemblyregister as exhibited in the current embodiments. As a result, in thesedesigns, the sensor was mounted only by metal-to-metal interconnectionsbetween the pedestal, the bottom pressure fitting, and the aircraftsystem base, which resulted in electrical conduction between all ofthese components. Therefore, there was no insulative mounting and thesensor could only be rated at 500 VAC.

In various embodiments of the current design, the pressure port pedestalfloats within the housing and is mounted therein by virtue of thedielectrics which surround it. These various insulated members cause thepedestal to be packed tightly within the sensor assembly register. Thus,the pressure port pedestal and sensor assembly is mounted within theregister without any interconnections which are electrically conductive.

Because of the high pressures (e.g. 4500 psi) to which certainembodiments are subject, and because there is no fixed mounting of thepressure port pedestal/sensor assembly, it is advantageously retainedand packaged securely within the sensor housing. This cannot beaccomplished by the dielectric elements alone, at least in certainembodiments. Therefore, in various embodiments, the sensor assemblyregister plays an important role in registering and retaining (e.g. atleast by exerting a compression force on the components) thepedestal/sensor assembly within the housing and, in particular, withinthe base. Thus, as shown in FIG. 2, the sensor assembly register 40 isprovided with a plurality of external threads (at least 3 threads) whichare received by the internal threading of the base 14. By this mountingtechnique, the pedestal/sensor assembly and the various insulativeelements (i.e. dielectric members) “float” within the housing.Furthermore, the register 40 exhibits an open upper cylindrical sectionwhich allows the sensor some room for movement due to furthercompression of these elements, when the pedestal is subjected to highpressures.

Due to the elongated design of the pedestal, it has sufficient length toreceive various dielectric and insulative elements. These elementssurround the pedestal/sensor assembly and allow it to be packagedsecurely within register and outer housing. This elongation alsoprovides the height necessary for the sensor assembly register 40 to beable to be placed over the sensor assembly and secure these elements tothe base 14 of the housing with a threaded connection, as explainedabove. That is, the sensor assembly register serves to provide acompression force to the various elements discussed above. Theelasticity of the dielectric components, as well as the washers andO-rings seals, allow them to be compressed into the floating mountingdescribed above.

The bottom of the base 14 is provided with a small hole which comprisesthe pressure port. The pressure port pedestal is situated directly abovethe pressure port and has a hollow interior portion which communicatesthe observed pressure to the thin-film sensor mounted atop the pedestal.

With reference to FIG. 3, it will be noted that various components havethicknesses which are sufficient to provide the dielectric advantages ofthis embodiment. Thus, nylon insulator spacer or insert 28 c has athickness of about 0.062 in. The O-ring seals 30 a, 30 b are preferablyof the 2-14 and 2-105 type, respectively. The lower insulator washer 28b has a thickness of about 0.090 inches. The diameter of thesecomponents is sized depending upon the diameter of the housing and canbe adjusted. Accordingly, in these embodiments, as noted above, thediameter is slightly undersized to provide for the use of the dielectricpotting material 54 described above and illustrated in FIG. 1. The gapbetween the circumference of these dielectric washers and the interiorsurface of the housing or cover is about 0.070 inches, to allowinsertion of the potting material. In addition, the upper insulatorwasher 28 a has a base thickness of about 0.090 in. and the shoulder 50has a thickness of about 0.073 in. The fourth insulator washer 28 d hasa thickness of approximately 0.70 inches.

In conclusion, the thin film sensor of the present embodiments provideimportant advantages over prior thin film sensors and MEMS sensors.

Embodiments

Disclosed embodiments include a system for a high voltage rating thinfilm sensor assembly. The system can comprise a housing containing thethin film sensor assembly. The housing can comprise a base and a cover.The housing can also have an elongated pedestal with the thin filmsensor mounted thereon to form the thin film sensor assembly. Thepedestal can have a flange formed on the circumference of the pedestal.At least two dielectric components can surround the pedestal andsandwich the flange. The dielectric components can be configured toelectrically insulate the assembly within the housing withoutmetal-to-metal interconnections. Based on these features (andpotentially others), the assembly can withstand voltage peaks betweenabout 500 VAC and 1500 VAC. A register can be fixedly mounted to thebase and within the housing. The register and the base can contain, atleast in part, the dielectric components within a hollow portion of theregister and the base. The register can exert a compression force on thedielectric components, thereby mounting the assembly within the housing.

In the above system, the thin film sensor assembly can comprises a thinfilm pressure sensor. The base can comprises a pressure port and thepedestal can comprise a hollow interior conduit configured tocommunicate a pressure to the thin film pressure sensor. The registercan align the pedestal conduit with the pressure port opening. At leasttwo additional dielectric components can be situated within the registeror the base for mounting the assembly within the housing. The dielectriccomponents can comprise insulators made from a polyimide material. Theinsulators can comprise nylon washers. The register can have a lowerportion configured for threaded engagement with the base to form acomposite pressure fitting. The pressure fitting can be configured towithstand pressures of up to about 4500 psi.

Described embodiments also include a method for assembling a highvoltage rating sensor package. The method can comprise providing ahousing configured to contain a thin film sensor assembly. The housingcan have a base, a cover, and an elongated pedestal having the thin filmsensor mounted thereon to form a thin film sensor assembly. The methodcan include inserting the thin film sensor assembly within the housingand mounting the thin film sensor assembly within the housing using atleast two dielectric components surrounding the elongated pedestal. Thedielectric components can be configured to electrically insulate theassembly within the housing without metal-to-metal interconnections.Thus, the assembly can be electrically floating within the housing andcan withstand voltage peaks between about 500 VAC and 1500 VAC. Themethod can also include registering the assembly to the base and withinthe housing, and applying a compressive force to the dielectriccomponents. This can allow the assembly to electrically float within thehousing while being fixedly mounted therein.

The above method can further comprise sandwiching at least twodielectric components around a flange formed on the pedestal. It canalso include inserting a third dielectric component within the housingto surround the thin film sensor. A pressure port can be formed in thebase and the method can include registering the pedestal in the base soas to be adjacent the pressure port. The method can further compriseinserting a fourth dielectric component in the base adjacent thepedestal and the pressure port. The method can include registering thethin film sensor assembly to the base using a threaded engagementbetween a sensor assembly register and the base. The compressive forcecan be applied by the threaded engagement. The method can furthercomprise securing a circuit board to the thin film sensor assembly.

Described embodiments include an isolation and alignment apparatus for athin film pressure sensor. The apparatus can comprise a base. The basecan have a securement feature configured to connect to a pressurizedsystem. The base can also have an opening for access to a measurementportal in the pressurized system, the opening configured to allow fluidcommunication between the interior of the pressurized system and aninterior portion of the apparatus. The apparatus can also have: a mount;a strong rigid cover configured to connect to the base and surround theinterior portion of the apparatus; and an elongate pedestal, sized tofit inside the cover. The elongate pedestal can have: a tip configuredto provide a mounting support for a thin film pressure sensor; anelongate open interior passage terminating at the tip for fluidcommunication between the measurement portal and the thin film pressuresensor; and a feature that protrudes laterally from the elongate axis ofthe pedestal. The apparatus can also have multiple isolation bodiesconfigured to surround and electrically isolate the elongate pedestalfrom the base and the cover; and an interior securement deviceconfigured for installation within the cover. This installation can:avoid physical contact with the sensor or the pedestal; secure thepedestal in place by holding the multiple isolation bodies tightlyagainst the laterally protruding feature of the pedestal; and maintainthe pedestal's position with respect to the opening and within thecover.

The apparatus described above can also include the following features.The base, cover, pedestal, and internal securement device can all bemetal. The isolation bodies can all be dielectric. The pedestal'selongate open interior passage can be sized to improve accuracy ofpressure readings without adjacent turbulent fluid flow. The internalsecurement device can include an open space surrounding the sensor anduse a threaded connection with the base to secure the pedestal in place,hold the multiple isolation bodies tightly, and maintain the pedestal'sposition. The apparatus can additionally comprising a filler dielectricmaterial that substantially fills remaining space within the cover notoccupied by the pedestal, internal securement device, isolation bodies,and any supporting structures. In the apparatus, the cover can beattached to the base with a threaded connection that is separate fromthe threaded connection of the internal securement device. Moreover, thelength of the pedestal, dimensions of the isolation bodies, thickness ofthe filler dielectric material, dimensions of the cover, space aroundthe sensor, and dielectric properties of all non-metal features can beselected and configured to allow the sensor to continue working when thebase and cover are subjected to up to 1500 Volts.

TERMINOLOGY AND CONCLUSION

Reference throughout this specification to “some embodiments” or “anembodiment” means that a particular feature, structure or characteristicdescribed in connection with the embodiment is included in at least someembodiments. Thus, appearances of the phrases “in some embodiments” or“in an embodiment” in various places throughout this specification arenot necessarily all referring to the same embodiment and may refer toone or more of the same or different embodiments. Furthermore, theparticular features, structures or characteristics may be combined inany suitable manner, as would be apparent to one of ordinary skill inthe art from this disclosure, in one or more embodiments.

As used in this application, the terms “comprising,” “including,”“having,” and the like are synonymous and are used inclusively, in anopen-ended fashion, and do not exclude additional elements, features,acts, operations, and so forth. Also, the term “or” is used in itsinclusive sense (and not in its exclusive sense) so that when used, forexample, to connect a list of elements, the term “or” means one, some,or all of the elements in the list.

Similarly, it should be appreciated that in the above description ofembodiments, various features are sometimes grouped together in a singleembodiment, figure, or description thereof for the purpose ofstreamlining the disclosure and aiding in the understanding of one ormore of the various inventive aspects. This method of disclosure,however, is not to be interpreted as reflecting an intention that anyclaim require more features than are expressly recited in that claim.Rather, inventive aspects lie in a combination of fewer than allfeatures of any single foregoing disclosed embodiment.

A number of applications, publications, and external documents may beincorporated by reference herein. Any conflict or contradiction betweena statement in the body text of this specification and a statement inany of the incorporated documents is to be resolved in favor of thestatement in the body text.

Although described in the illustrative context of certain preferredembodiments and examples, it will be understood by those skilled in theart that the disclosure extends beyond the specifically describedembodiments to other alternative embodiments and/or uses and obviousmodifications and equivalents. Thus, it is intended that the scope ofthe claims which follow should not be limited by the particularembodiments described above.

What is claimed is:
 1. A system for a high voltage rating thin filmsensor assembly, comprising: a pedestal having a thin film sensormounted thereon to form the thin film sensor assembly, the pedestalhaving a flange formed on the circumference of the pedestal; and atleast two dielectric components surrounding the pedestal and sandwichingthe flange, the dielectric components configured to electricallyinsulate the assembly from metal-to-metal interconnections, whereby theassembly can withstand voltage peaks between about 500 Volts AC (VAC)and 1500 VAC.
 2. The system of claim 1, wherein the thin film sensorcomprises a thin film pressure sensor.
 3. The system of claim 1, furthercomprising a housing base comprising a pressure port, wherein thepedestal comprises a hollow interior conduit configured to communicate apressure to the thin film sensor.
 4. The system of claim 3, furthercomprising a register fixedly mounted to the housing base and configuredto align the pedestal conduit with an opening of the pressure port. 5.The system of claim 4 wherein at least two additional dielectriccomponents are situated within the register or the housing base formounting the assembly within the housing.
 6. The system of claim 1wherein the at least two dielectric components comprise a polyamide orpolyimide material.
 7. The system of claim 1 wherein the at least twodielectric components comprise nylon washers.
 8. The system of claim 4wherein the register comprises a lower portion configured for threadedengagement with the base to form a composite pressure fitting, wherebythe pressure fitting is configured to withstand pressures of up to about4500 psi.
 9. A method for assembling a high voltage rating sensorpackage, comprising: providing a pedestal having a thin film sensormounted thereon to form a thin film sensor assembly; and mounting thethin film sensor assembly using at least two dielectric componentssurrounding the pedestal, the dielectric components configured toelectrically insulate the assembly from metal-to-metal interconnections,whereby the assembly is electrically floating and can withstand voltagepeaks between about 500 VAC and 1500 VAC.
 10. The method of claim 9,further comprising sandwiching the at least two dielectric componentsaround a flange formed on the pedestal.
 11. The method of claim 9,further comprising inserting an other dielectric component to surroundthe thin film sensor.
 12. The method of claim 9, further comprising:providing a housing base including a pressure port; and inserting thethin film sensor assembly into the housing base registering the pedestalin the housing base so as to be adjacent the pressure port.
 13. Themethod of claim 12, further comprising inserting an other dielectriccomponent in the housing base as to be adjacent to the pedestal and thepressure port.
 14. The method of claim 12, wherein registering pedestalin the housing base uses a threaded engagement between a sensor assemblyregister and the housing base.
 15. The method of claim 14, whereincompressive force is applied by the threaded engagement.
 16. The methodof claim 15, further comprising securing a circuit board to the thinfilm sensor assembly.
 17. An isolation and alignment apparatus for athin film pressure sensor, the apparatus comprising: a base having: asecurement feature configured to connect to a pressurized system; anopening for access to a measurement portal in the pressurized system,the opening configured to allow fluid communication between the interiorof the pressurized system and an interior portion of the apparatus; apedestal having: a tip configured to provide a mounting support for thethin film pressure sensor; an elongate open interior passage terminatingat the tip for fluid communication between the measurement portal andthe thin film pressure sensor; and a feature that protrudes laterallyfrom the elongate axis of the pedestal; and multiple isolation bodiesconfigured to surround and electrically isolate the elongate pedestalfrom the base.
 18. The apparatus of claim 17, wherein: the base andpedestal are metal; the isolation bodies are dielectric; and thepedestal's elongate open interior passage is sized to improve accuracyof pressure readings without adjacent turbulent fluid flow.
 19. Theapparatus of claim 18, further comprising an interior securement deviceconfigured for installation within the cover such that it: avoidsphysical contact with the sensor or the pedestal; secures the pedestalin place by holding at least one of the multiple isolation bodiestightly against the laterally protruding feature of the pedestal; andmaintains the pedestal's position with respect to the opening.
 20. Theapparatus of claim 19, wherein the length of the pedestal, dimensions ofthe isolation bodies, space around the sensor, and dielectric propertiesof all non-metal features are configured to allow the sensor to continueworking when apparatus is subjected to up to 1500 Volts AC.